Many fluid chemical products used in industry, agriculture, and by consumers have a negative environmental impact if not properly used, stored, applied, handled and shipped. Many of such fluid chemical products which are potentially environmentally hazardous are stored and shipped in expensive closed containers specially designed to safely enclose the fluid and such containers, such as those used with agricultural fertilizers, are leased or rented by the consumer with the intention of the container being returned to an authorized dealer for refill. However, because of the high quality of the container consumers sometimes retain the containers for use for other purposes than which they were intended, and the containers may be refilled with fluids other than that for which they were designed, or originally contained.
As the manufacturer of chemical fluid products shipped in such containers may ultimately be held liable for damages arising from improper refilling of such containers and receptacles concern exists that the unauthorized refilling of containers originally used with fluid having an environmental impact may result in bodily harm or severe environmental damage. Many fluid chemicals shipped in containers may become explosive, or highly pressurized, if mixed with other agents improperly introduced into the container and fluid security systems preventing such occurrences have not been available which are practical and feasible.
A particular instance wherein fluid security of the aforedescribed type is highly desirable is with agriculture products wherein the farmer consumer rents or leases a container of fluid chemical fertilizer or cleaner, and the consumer attaches a coupling to the container coupling to permit the desired dispensing of the fluid. Thus, the consumer will have a coupling compatible to the fluid container coupling and the consumer will have the equipment by which fluids could be introduced into the container unless the container coupling prevents such occurrence. Heretofore, security couplings which permit authorized container refill have not been practical in that fluid flow therethrough is necessary to permit the authorized dispensing of the fluid chemical from the container by the consumer and although the use of a simple check valve prevents refilling by the consumer such a check valve also prevents an authorized dealer for the fluid chemical from refilling the container.
It is also necessary that couplings used with fluids having adverse environmental impact not spill or release the fluids except when intended, and complicated couplings using a plurality of valves, including a check valve, will trap fluid within the coupling body itself which may become highly pressurized due to environmental heat causing such confined fluid to leak from the coupling into the atmosphere and surrounding ground.
It is an object of the invention to provide a no-spill fluid security coupling system which is relatively economical to manufacture, concise, automatic and foolproof permitting unidirectional flow through a coupling part during dispensing and preventing unauthorized bidirectional coupling flow.
Another object of the invention is to provide a no-spill fluid security coupling system of economical construction wherein a primary coupling selectively receives secondary couplings, such secondary couplings being either of the consumer type permitting unidirectional flow for consumers use, or permitting bidirectional flow by authorized personnel employing a secondary coupling part different than that employed by the consumer.
Yet another object of the invention is to provide a no-spill fluid security coupling system employing a primary coupling part and "consumer" and "dealer" secondary coupling parts of different construction wherein attachment of the consumer part to the primary coupling part permits only unidirectional flow from the primary part, and the dealer coupling part permits bidirectional fluid flow through the primary part permitting receptacles associated with the primary part to be refilled.
A further object of the invention is to provide a no-spill fluid security coupling system employing a primary receptacle coupling part selectively connectable to consumer and dealer secondary coupling parts, the secondary coupling parts automatically controlling the primary coupling part for unidirectional or bidirectional flow therethrough.
Another object of the invention is to provide a no-spill fluid security coupling system wherein coupling parts may be interconnected by relative axial movement, and only axial movement is required to achieve the security operation of a plurality of valves within the primary coupling part selectively preventing bidirectional fluid flow through the primary part.
Yet another object of the invention is to provide a no-spill fluid security coupling associated with a receptacle wherein a plurality of axially spaced valves are located within the coupling part and fluid trapped between the valves is automatically discharged to the receptacle upon a predetermined fluid pressure existing in the trapped fluid.